Dexmedetomidine sedation in children after cardiac surgery*

Objective To study the efficacy and safety of dexmedetomidine before and after early extubation after pediatric cardiac surgery. Design Prospective, observational study. Setting University hospital pediatric intensive care. Participants Infants and children undergoing cardiac surgery. Interventions The 141 patients, depending on the treatment period, were divided between: 1) usual, postoperative, continuous, intravenous sedation with chlorpromazine, midazolam, or fentanyl (n = 85); and 2) treatment with dexmedetomidine, 0.4 to 0.6 microg/kg/hr (n = 56). Sedation was titrated to reach a Ramsay score of 4 or 5 by administering rescue boluses, as needed. Measurements and main results The primary and secondary study end points were efficacy of sedation and frequency of adverse events, respectively. The numbers of rescue boluses needed and the proportion of ineffectively sedated patients were similar in both groups. The frequency of bradycardia or hypotension in the dexmedetomidine group was 21.4% (8.2% in usual sedative group, p = .04), requiring interventions to restore hemodynamic stability in 5.3% of patients (0% in usual sedative group, p = .06). Rates of respiratory depression (8.2% vs. 0%, p = .04) and involuntary movements (15.3% vs. 3.6%, p = .01) were higher in the usual sedation group. Conclusions A usual sedation regimen and dexmedetomidine were similarly efficacious. Although dexmedetomidine was associated with a lower rate of respiratory depression, it caused a higher rate of adverse hemodynamic events, which might be a concern in hemodynamically unstable patients.